The prior art describes various devices for compressing a gas phase and for pumping a liquid phase, or for compressing a gas phase and a multiphase phase.
One procedure consists in using suitable single-phase equipments for each phase, associated with phase separation devices.
Single-phase compression of a gas and pumping of a liquid at high pressure generally requires a large number of equipments, for example one or more compressors for compression of the gas, one or more heat exchangers for cooling the gas after compression, one or more pumps for pressure rise of the liquid, one or more devices for mixing the phases, a gas and liquid separator placed upstream from each compression section, pipe connections, valves, instrumentation and a complex regulating system for keeping the assembly in good working order. Such a system is relatively unwieldy and expensive.
It is also well-known to compress a fluid comprising a gas phase and a liquid phase in order to mix them at high pressure, by means of a positive-displacement or rotodynamic type multiphase compression device equipped with helical axial flow impellers. The major drawback of positive-displacement machines is that they are heavy and bulky.